In case the air gap in an induction motor is increased____________?
Correct answer: B. the power factor will decrease
- A. the magnetising current of the rotor will decrease
- B. the power factor will decrease
- C. speed of motor will increase
- D. the windage losses will increase
Explanation
Increasing the air gap raises magnetic reluctance, so the motor draws a larger magnetising current and its power factor falls. The phrase “magnetising current of the rotor” is technically imprecise because magnetising current is supplied by the stator.
Last updated
Practise Electrical Machines
1,061 free Electrical Machines MCQs from Electrical Engineering, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Electrical Engineering questions like this
Electrical Engineering is on 2 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
5 H.P., 50-Hz, 3-phase, 440 V, induction motors are available for the following r.p.m. Which motor will be the costliest ?
A 220 V D.C. generator is run at full speed without any excitation. The open circuit voltage will be_____________?
A 3-phase 440 V, 50 Hz induction motor has 4% slip. The frequency of rotor e.m.f. will be____________?
A 3-phase induction motor delta connected is carrying too heavy load and one of its fuses blows out. Then the motor______________?
A 3-phase induction motor stator delta connected, is carrying full load and one of its fuses blows out. Then the motor_______________?